North Korean leader Kim Jong Un delivers a surprise New Year address in Pyongyang on Tuesday.

By NBC News wire services

SEOUL, South Korea -- North Korean leader Kim Jong Un called for an end to confrontation between the two Koreas, technically still at war in the absence of a peace treaty to end their 1950-53 conflict, in a surprise New Year speech broadcast on state media.

The address by Kim, who took over power in the state after his father, Kim Jong Il, died in 2011, appeared to take the place of the policy-setting New Year editorial published in leading state newspapers.

But North Korea has offered olive branches before and Kim's speech does not necessarily signify a change in tack from a country that vilifies the United States and U.S. ally South Korea at every chance it gets.

North Korea, which considers North and South as one country, the Democratic People's Republic of Korea, is banned from testing missile or nuclear technology under U.N. sanctions imposed after its 2006 and 2009 nuclear weapons tests.

"An important issue in putting an end to the division of the country and achieving its reunification is to remove confrontation between the north and the south," Kim said in the address that appeared to be pre-recorded and was made at an undisclosed location.

"The past records of inter-Korean relations show that confrontation between fellow countrymen leads to nothing but war," he said.

Economic reform?Kim also called for improving living standards of his impoverished nation, with passages in his speech acknowledging the poor state of the country's economy that has long lagged behind the rest of the region.

But Kim gave no indication whether he plans to introduce economic reforms or allow free enterprise, except to say the economy should be underpinned by science and technology.

"The industrial revolution in the new century is, in essence, a scientific and technological revolution, and breaking through the cutting edge is a shortcut to the building of an economic giant," he said.

The speech avoided harsh criticism of the United States, its wartime enemy. North Korea has used past New Year's editorials to accuse the Washington of plotting war.

In other signs of changes in the country -- at least at a superficial level -- North Korea also had its first grand New Year's Eve celebration, with residents of the capital treated to the boom of cannons and fireworks at midnight.

In Pyongyang, residents danced in the snow at midnight Monday to celebrate the end of a big year for North Korea, including the 100th anniversary of the birth of Kim Il Sung and the first year of Kim Jong Un's leadership. Fireworks lit up the cold night sky, and people stood in fur-lined parkas, taking photos and laughing and dancing with each other in plazas.

High tensions with South remainThe New Year address was the first in 19 years by a North Korean leader after the death of Kim Il Sung, Kim Jong Un's grandfather. Kim Jong Il rarely spoke in public and disclosed his national policy agenda in editorials in state newspapers.

"(Kim's statement) apparently contains a message that he has an intention to dispel the current face-off (between the two Koreas), which could eventually be linked with the North's call for aid (from the South)," said Kim Tae-woo, a North Korea expert at the state-funded Korea Institute for National Unification.

South Korean navy ships have found what appeared to be debris from the rocket launched by North Korea this week. NBCNews.com's Alex Witt reports.

"But such a move does not necessarily mean any substantive change in the North Korean regime's policy towards the South," he added.

The two Koreas have seen tensions rise to the highest level in decades after the North bombed a Southern island in 2010, killing two civilians and two soldiers.

The sinking of a South Korean navy ship earlier that year was blamed on the North but Pyongyang has denied it and accused Seoul of waging a smear campaign against its leadership.

Last month, South Korea elected as president Park Geun-hye, a conservative daughter of assassinated military ruler Park Chung-hee, whom Kim Il Sung had tried to kill at the height of their Cold War confrontation.